Ajax PHP Frameworks
These libraries are comprised of a JavaScript part for the browser side,
and PHP scripts working on the server.
Here is a list of the main open source solutions among which some are part of this Comparison of web frameworks. Sources of the tests are provided.
The highest figures, the number of requests per second, are the best test results.The faster framework are for the Go or Python languages. The fastest PHP framework is Code Igniter.
These tests are not significant actually because it is access to databases that slow down the most applications and displaying a "Hello World!" message is not sufficient to evaluate a tool, particularly because PHP has a high startup time while other tools work differently, staying active between successive launches of the application.
Ajax and PHP frameworks
They are all compatible with PHP 5.
PradoPrado is based on components, actually objects (more than 700), event-driven like JavaScript. It uses the MVC model. It includes HTML widgets too.
What does not give confidence however is that the site is a mixture of pages in English and French with many broken links.
Symfony is a framework and set of components for building elaborate web applications. Eases the use of databases. Among the most notable users, Dailymotion demonstrates that its possible to support heavy loads. This contradicts the results of the benchmarks.
The site gives six reasons for choosing this framework: its popularity among developers, its sustainability provided by the wider community, the many sites that use it, the constant search for innovation, many resources, interoperability through compliance to standard related to PHP.
Tigermouse is aimed at prototyping and modeling, Web application creation and reusability of components. This framework looks as Java and is built in the Model-View-Controller architecture
PHP only frameworks
Such pure PHP framework may be completed by a JavaScript Ajax framework but it is not part of it.
Code IgniterCode Igniter is a sSet of class for helping in building a Web application as blog, news, etc.
CakePHP is a fast, scalable framework with plugins. CakePlate distribution is a tool ready to use without complicated configuration with all commonly used extensions.
FuelPHP is designed on the view/controler model, it intends to combine the qualities of other frameworks but theirs drawbacks. It prides itself on offering a "Route directly to closures", and I forward you to the documentation on the site for clarifying.
Photon is operating on Mongrel2, a server for Web applications, it is a fast and optimized framework for reducing access to the server.
See also...
HTML 5 frameworks. They work on the client side but provide greater interactivity with the server.